Tests on a four-cycle automobile engine

G2I.43
B27

TESTS ON A FOUR-CYCLE
AUTOMOBILE ENGINE

D. 0. BARRETT and C. W. KORGAN

Armou)' institute of Teehnology
i 908

llliaois Institute
of Teclmoiogy

UNIVERSJTYUBRARIES

z^T 102

Barrett, D. 0.
Test on a four-cycle
automobile engine

For Use In Library Only

TESTS

ON A

FOUR-CYCLE
AUTOMOBILE ENGINE

A THESIS

PRESENTED BY

Dwight O. Barrett

and

Charles W. Morgan

PRESIDENT AND FACULTY

OF

ARMOUR INSTITUTE OF TECHNOLOGY

FOR THE DEGREE OF

BACHELOR OF SCIENCE IN MECHANICAL ENGINEERING

HAVING COMPLETED THE PRESCRIBED COURSE OF STUDY IN

MECHANICAL ENGINEERING
June 1st, 1908

ILLINOIS INSTITUTE OF TECHMOLOG\
PAUL V GALVIN LIBRARY
35WEST33RDSTREE^

.^ ^ .'^ ^ CHICAGO IL 60616

on a ~

The -?no;ine upon vfnich these test3 were con-
ducted is a four-c-'linder ''our-cr-le autono'oile
en^rine, vianufactured oy the Continental "otor "f=^.
Co., "\i3ksgon, "ich. '"he c^'linders are cast in

pairs and hare a here o f 4 3/8 inches and a stroke
of 4 3/1 inches. The j ur:p spark s^rsten of iirnit-

ion is iised.

~efor^ corjr.or.cin- v/ork upon the enrrine it v:as
fourd that one of t'le connectin—rod hearings r/as
loose and the head of the scre\7 holding the he- r-
inp- ca-o had 'oeen icraping on t!a3 inner surface of
the crank-case, v.hich is of aluj:iinur.i. I'his led

to a r.ore co--.plete inresti.ration of th- condition
of the engine.

The enf-r'ne -r s hoisted '^7 "leans of a hea-^n'-
rope and then turned orer in the rope nnd replac-
ed upon the cast-iron siipportin- ''.ase. "lie lo\7-
er half of the crank-case hein- rer.oved, it -7as
found that the crank-shaft hearin-r Tor each con-
nectinr-pod h-d heen scored a"-out 1/1-- inch deep.

20757

AltWOtTH
INSTITUTE OF TECHNOLOOI

A.UMf>va

The main "bsarinrrs, however, Vv'ere in rood condition.
The tv:o out?r TDe-rin.'rs are each luhricated "by r.ieans
of cor.pression f-rease cups "but the inner hearing
depends iijion the fiplash fro-n ths cranh-case. ""v-

identl-^, the oil had been allov.-e;l to -at too Iott in
the cass or else the oil-holes in the nonncctinp;-
rod had hscoine filled thus a-llowino; oil tc rret in
only at the sides.

It was then decided to co-^.plet^l''- overhaul
the eno-ino, '^he cra.nh-.-'iaft was r^jnoved and the

connectin'T-rod hearings decreased in size frcr: 1 1/2
inches to 1 7/15 inche-?. "he "lain ■!:e- rings were

not touched, retaining their original diar.ieter o?
1 1/? inches. ^lese are three in nu-v:er, one at

each end and one at the center of the crank-case.
The ccnnec-'-in'?--rcd "-^earings are 2 3/-i inches in
length and the r.ain he-^rinr-s 3 and 3 1/2 inches.
?he two en-i hearings arc forr.ed hy the tipper and
lower halves of the cranh-case. Ml hearings

are supplied with ^-:ron?:e hushings. It vr s , of

course, necessary to diminish the size of the con-

nectiri^-rod 'ousliiri'^'? to 1 7/15 inches. They were
'Dored out and ther. filled vrith nickel '^^.Voitt pour-
ed around nn r^r'-or slight 1-' smaller than the shaft.
Tliey Tvere then scraped to size en th^ cr^rik-~haft.

One of th^ -.-.Trist-pins ^Tas found to "b:^ ':rohen
and this v/as replaced. These are of tool-steel
and hardened, having a diar.eter of 7/2 inches.
The pistons are. each equipped -Tith three cast-iron
snap rin^rs located ne-^r the upper ''nd. "^le
length of the piston is 7 inches.

Several of the valves v/ere found to he rust"^
as vrater had prohahly --rotten onto their, fron the ex-
haust pipe, having heen previouslv used in keepin?^
this pipe cool. All valves 'v7ere s-round, first
with enerv flour and then v;ith rround '-lass.

It had ^:ecn discovered tha': an ahnonnal a:nount
of oil -.Tas consujiied fron the crank-ca^e, this ^zeinq.
splashed up on the clinder vralls and carried out
■.7ith the enr-ine e:ch?,ust. To prevent this tv.'O sheet-
inetal haffle plates •.7'^re placed ir the upper half
of the crank-case, eac.'i having two slots for the

free \7or''<:?,r.j' of f.-.e connectir.'^-rods.

It v!R5 ori-'ir.all''' ir. tended, in t-stinrr tlie
en^^ine , to connect at the fl^'^^rheel end a direct-
current -enerator , ur^.ine as a. resistance a v;at?r
rheostat. ^or this purpose the en^^ine was turn-
ed thrix 90 d?cre>3S on its foi,r.-:dation to allOT? r.ors
roo:n,

CAFSUEATIOIT.
The carhuretor vised on the enrrine is ~ 1 1/4
inch Schehler "^lodel Tl" , arran-Ted 'Tith an au::il-
iary air inlet. The main air pipe is not risible
in the photograph hut is simply a curved hrass tuhe
which "bends up "behind the carhuretor. "lis car-
huretor is one of the hest on the rnarhet an:l its
action is as follows: The rasolino fro::" the supply
"'■anh, located at the rear of the en^^ine , rraritates
do':'7n thru the inlet valve until the gasoline ch^n-
her fills ::uTiciently to raise the float and close
the valve, 'T:iile the en.o-ine is under operation
this little valve is autonaticallv opened and closed
by the float, thus naintaining a practicall" con-

AltMOTTH
INSTITUTE or TBCHNOI^JOX

ARMOUH
jmsnXOTE OF TBC3HN0100I

-7-

stant level of r^-- soline in the suppl" ch^.rr.'ber.
Upon each suction stro!:3 of the engine - "snall a-
nount of gasoline passes thru th3 needle yalve , is
ator.ized there"::;' and ni:ce3 \7ith the air vfnicr. is
draT.7n in thru the air inlet and aur'iliar-; openin,r^.
On low loads "guTficient air can "oe o'ctained thru
the main air inlet, "out on he-T-r loads rrhon ".lore
air is needed the suction heco:-.es sufficient to
open the au-iliar- air valve and let in the rerr-
uisite sup-Dly. "The -r.ixt^ire of air and gasoline
vapor, after le-^vinc the r.ixino- chamher, passes up
thru the inlet valve into the cylinders.

The valves on this engine are all nechanical-
ly operated hy pus'i-rcds fror. the tv/o-to-one reduc-
tion cam-shaft, this heing driven l:y ^orass spiral
gears. All valves are interchar.^eahle '^nd are
1 3/4: inches in dianeter. T'le settings of these
valves r.av he readil:- understood frc- the scheme
on the fcllovdng pa-^e. The variation in the
opening- and closing of the valve? :r.ay he due to

t.:**

f-,i2 u.

ABMOtrS
mSTETDTE OFITSCKNOUX**

three cause ^.; 1. The cans rtia"'' not "oe set exp.ctly

ISO degrees ap^.rt , 2, The cams :iiaY he vrcrn, 3,
The push-rods r-ay not he of e:-:actl" the SRino
length.

ir]-TTI01T.

The jurrp-sparh ifmition sTsten is di-'crai'iT.iat-
icall'' shc-m on the "cllovnnr' pare. Tv/o ?our-

Tolt stora^'e cellr; ^'^ero used for supp^"in.'^ the pri-
inarT c-tirrent. "Hae hi r~ -tension current was ohtained
fron four Tplitdorf induction coils. The ti:r.er

tised Tvas the "Connecticut" -Ahic"': has a cono-shaped
roller for •.-.•'.ahing the ccnt-.ct. T'.is produces a.
v/iping e!'fect ijvhich heev'S the contacts clean.

Tlie spar!< plu'^s fon-ierl ' used on the engine
had irdca insulation '^ut tj.ose rapidly hecai-ne sooted
and could not h? readily cleaned. The "hever-iiss"

plug VL-as then substituted an' no trouhle has r^ince
heen experienced. i^orc-lain insulation is ysod

and the pluo; can 'ce easil" dicasser.'-led for clean-
inc-. The plu<^s are placed over the inlet yalves.

AHMOtra

1NSTIXUT£ OF T£OENOI.OOZ

-in-

iriHRTCATIO:-,

The cr-'"-,n'':-case of the enirine, tho accessi'!ole
for ins-pection, is oilti'^'t -an,! the splash svstea
of luhrication is usod on all four cran'^s an -I the
canter r'.ain "oearir.'-. The outer •.■-.ain oearinf^r-?

are lu':^ricate:l hy means of coripression ^r-^ase cup^.
The other parts of the engine, such as carn-shaft,
piston?5, etc., receive their suppl - fron a "cCord
8-point force- reed lu':ricator driven V-- a helt
fro--: the r-.ain shaft. ^orae oil is, c" course,

splashed 'x' th.-? h-ffle-plates onto the cylinder -.vails.

One rallon of ""^^acu^u-. "" oil -.ras used in the
luT^ric^tor "!:;ut a lighter oil -.t-s afterward o'ctained
fron th- ^erroorn Pru- C^ Cher.ical ^o. 'i'he heav-

ier oil seer.s to -ive tlie "cest results.

TlQ,UIP'''n^ITT for TP^TI^'^C-.
The engine i.vas arranged for testin'- in the
folio --in? nanner: The -jasoline suppl" tank was a
cylindrical four-~allon one -7ith n 5/8 inch .^a.re-
.-rlass open at the upper end. Tliis tanh was

placed on one pan of a l^air-anhs >? lance v.hich v;ould
weidi acouratel ' to one -rar^. The msoline --as

-1?.-

siplione". frcri the j^re-rlas;^ thru " l/i-ir.ch
copper tuhe.

"o detemirie the ievoloped horse-pov/er a Prony
"brahe having an ef.rrective length of rE5 inclies '■.•as
used. Tlie weiTht of coolin!r -:ater \Ta3 chtained

\Tith weighing tanks suitaT:!" arranged. Tenpera-

tv.res or the inlet and ov.let cooling v:ater -:ero de-
ternir.ed vjith Centigrade themorneters graduated to
0.01 de-rree. A I'artnann <:: 3raiin --illivolt-eter ,

connected to a copper-cc-pper-con-tantan therr.ccoup-
le, was co--:-'.ared \7ith a ^.Hiipple tenperatiir- indi-
cator an' then used for deteraining the e-'haust tem-
perature hy inserting in the e:chaust pipe :ust he-
yond th3 r-.anifold.

The Tospitalier mano^r- h '^.=^scrihed on pa-^e 28
v;as connected to t-ic cylinders o-r running a l/8-inch
copper pipe fror: the sinograph "o a -.nail hrass
manifold containing the ends of 1/4 ^nch copper pipe'^
leading to each cylinder. ^to; coc>3 '.vere placed
in each cylinder head so that a>.ny c-linder could he
indicated as desirr-d.

-13-

AHMOCTB

■UfsriTUTB oe^

x3ccaNoi.oax

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AjaMOtra

ISSTIXVTE OF TKCHUOl-OO*

-14-

Tho rie-l'ol^ s'l^ ft connectior. fror: the r.ano-
p-rapli vr^.3 desimecT ''03'' the makers ~o he connected
to the main crnn"'--shaft of the eno'ine >7 a t^^per-
e-^. friction sleeve. This friction dovico vras
found v.ndesir^/'^le -nd therefore a single notched
sleeve •^ir.-.ilar to an auto cranh '.Tas suhstituted,
A.".''ter once c-ettin-- the nanoTraph in phase it re-
mains ^.0 and no further nd" v.strient is neces^ar'/.

The TESTS.

Two distinct sets cf runs v;ere made for de-
term.ining the rasoline consumption of the en.irine.
One set \7as ohtained under constant speed and rar-
iahl? load and the other under variahle speed and
constant load. J^uns v;ere a,lso miade to detorrdne
the variat^or of th-: hcrse-power -^ith sj)eed.

In all run'" the sparh lead v/as maint-^.ined
constant and the engine r3:-^.^lated . -ntirelv hy m.eans
of the throttle. In th- last runs the po-;er oh-
tained v;as the m.a^imxm''. 'rhich the enrine v-ould car-
ry for any length of tim.e. On the her'rrr loads it
v/as found di i'f icu.lt to.m.ain-^ain a constant speed

-15-

cortiuoucl-- so thnt short runs I-iad to "be made, be-
inc^ of only 1"=^ ^ninutes duration.

l^.eidin'-s Vv'erG t^J'r.er. of the follov/inr;:: v.-ei'-hts
of -gasoline r.nd ■r^ooling '^ater , ten:per?itur';s of inlet
?.nd ov.tlet ,i ac^cet v/ater and the roo-, erdiaust ter.-
perature , hra?ce load and speed.

The '--asoline used durin.cr the tests was pur-
chased as needed and hence it cannot "be said that
it had a coiistant henting value or "pscific grav-
itT. "^0 "'e sure that all ^.Tat^r v/as rer.oved from

the fuel it v;ao strained thru chaT.':ois "iihin.

before each run the engine \7as indicated
^'d.th the mano graph to see that it v;as in proper
v/orkin^e condition. f^-^^veral light spring indi-

cator cards ^vere tahen and cor: •■■-re:!., 'iliese

showed the variation of the valve settings ver'/
nicely.

rar'CusRio:! of ti"^?uxtr.

Prom the const^.nt-^peod-variahle-load runs
it was found that tha gasoline consufnption var-
ied inversely as the d.h.p. fro::: 4 to 12 h.p.

-16-

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AHMOTTH

niaxinjTE of rBCHNoi-ooir

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AJtMOlTB
JUSTITXJTE OF •«' •■

-18-

tecomin.'T a •rdniriim: of alDOut 0,38 Vo. per d.li.p.-hr.
p.t 15 hp. '^ho curve sjiowing the variation in

tlierir-al efficienc:/ ^vith d.h.p. for the B-r-e series
of runs sho\7S n. naxisvri efficienc-/' of ahout 17..?
per cc-r.t at.lS.'^^ h.p. The therr.al efficiently

he-'-on:- this point falls off verv rapidl-.

"^jTie curves plotted for constant-load-var-
ia-'r-le-npeed sho-^ that v;i •'■?.. p. load of 7.;" h.p,
tlie .trasoline consu".-ption "becories a minima of ap-
proxir.ate !•','■ 0.81^ Ic. per d,h,p,-hr. -.rhen the en-
gine is running at 585 r.p.n, "^he thermal effic-
ienc-, of course, re?;ches a r.aTrinum at the sair." spe9d.

The speed-load curve indicates r^ practicallv
direct variation of liorse-powsr v/ith speed up to
ahout 17 h.p. and a speed of 700 r.p.rn. The raa::-

ir.urr h.p. is ^'rcut 17.4 at "00 r.p.ivi.

'^onsiderin,'^ all the curves sone rp.ther in-
teresting conclusions na" "be drawn and soriie sugges-
tions offered for future testir.ff o? the engine.

TemenTDerincr that the :riaxir.ur.: econoriv for 7,63
h.p. v:as at '^S'^ r.p.:::. and for 7'^0 r.p.:-.. at 1 '^ h.p.

"19-

AHMotra

XNSHTPTE OP l-ECHNOtOOT

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AHWOTTH
INSTITUTE OF ITBCHNOLOOT

LIMMAIJV

AHSrotTB
niBXITDTE OJ- 1 fc<HNOl,..uy

--^4

it \70uli -eerii, that a'^ the horsG-pov:er was increased,
the economical speed also b-^ca:r.e r-reater. If sev-

erf?l sets of rurs --ere ■■ciade ":ith constant loads and

at varyin/? spe-ds as on pa-e 20 curves v:ould proh-
arly he ohtained sirilar to that one, hut --ith the
^iiinhrxm point ^^raduall" -.orinrr to a hi?^hor speed.
':^his -.Tould prohahlT rr^acli a certain point and from
then on the con^vnpticn 'Tovild he -reatlv increased
up to the r.:axiram caacity of th- enr^ine.

The h.r.. -speed curve hears this out as the
horse-pov/er reaches a niaxinviri and then drops ox^
for increasing speed-?. Some of the causes for

the decr-asc in h.p. -re; increased friction of
hearings, pistons and ^ears , v;ire-dra.v.;ing of the
irco-iing char<re thru the carl:uretcr a.nd inlet pas-
sa-es, increased inerti?. forces, incr-as?d -'-ind-

a^e .

It vrould he ir.tsre-~ting to r:alce several tests
on this en=:-ine ohtaininc curves si-.-.ilar to these on
T-an-esT--' and 20 and det?r-ine :ust hov; this econon-
ical point varie;- under different conditions.

""his engine is ra'^ed at 20 li.p, ■!:ut this rat-
ing i;i altop-etliar too hi'-'i. '""f course this pov/er
can he ohtained at the hi^-her spseds ":'ut this prac-
tice is ruinous to the en-ine. Then, arain, at
these speeds the -nrine would h3 verj v.'-steful of
rasoline md. properl'r it should ho ra.ted at its
r:ost econcrrdcal point. It v/as not considered ad-
visahle to operate the en'^ine at, speed-^ much ahove
7 50 r.p.r.i. It v/ould seer., then, th^t the proper
r^.ting of th? engine should be ahout Ir? h.p. at
7'"6 r.p.a. It is, to he deplored that /jnerican
huilders usual 1'" r^te t'leir enrine"^. nt very near
the :r.a::i;ruiTi power ohtainahle fror: the-;, thus allovr-
in£f no reserve for overloads,

Tho operation of the enf-ine, on the -.h-ole,
vr-3 re:"^ satisfactory especiall- after ;-- 1 1/1-
in'^li Tchehler "''odel '"" carhuretor had heen suh-
stituted for a 1-lnch ""'odd P", -fiich -.-s used in
the proliriinar'^ t^sts. The ""'odel '^" is •"uch
more easil ^ adjusted as the main air inlet is mere
nccessihle. In order to rot a finer control of

the t'lrot-^.le n, v.dr-, 'cent in the 'I'd r-., of n crank,
\7?is thre-^.ded. and passed thru a standard, 'oeins
attached at the one ond to the throttle lever
uhiich -vas of the p-ate t^rpe.

An improvement ^'/as made in the mano/i-raph for
the -cu-'pose of photographinp- the indicator cards.
An ordinary plate holder ^7as supplied hv the makers
for this purpose. A Prir-.o :^iln Pack Adapter v;as

fitted in its -olace and hv rriean^ of this twelve
cards v'ay he ■'■aken in succession, the packs hold-
ing one do sen films.

^ards \7ere taken f re ■ the en-^ine under nenrly
all conditions. It '.uas foun:. inpossihle, hovfever ,

tc develop th.^ films for sere reason :^o that none
are inclvided.

It is su/Tffested that, for future tTstin^r, of
this en<Tine, a dir-ct-cureent ^Tcrerator and \7ater
rheostat oe suhstituted for the Prony brake. The

load can onl" he r.aintair.ei cons'-ant on the hra!-e

--^7-

'cT liarinn- ^,n operator ther'^ cor.tii-:.uall''" ^-V.d. t'len
'vit'i th9 generator t>-ere is no v;nter used.

To calr/orate tlio -venerator a calibrated motor
ni'Tht l:e used or else it cculd "ce mounted on "rail
■"cearing" ir. tlie for";-, of a cradle ""n^uno'-ieter.
T^'aTin'T caliTorated it >)■'• means of Iznovm \7ei';'"_ts .giv-
ing certain tor-'ues the am:-:eter and voltmeter read-
ings coul' l:e used to o':tair tlie deTeloped horse-
pc-.rer.

ITcte. — A description o? the Ilospitalier manograph
v<'ill '^e found on the follovring pages.

Tr.e 3"0r^PITALIE';>CA'TK:TITli; ^'AHOC^KP::..

Tiie Hos-oit^.lier-^arpentier r-^rno^r-.p-i v.sed in
this test is an opticp.l 2ndic-tcr ir.Tontod 'cy Prof.
Fospitalier and manufacture ei -r/ the ^arpontier in-
stru-^-.ent hoiise , of Paris.

On the fcllov;ing page is shc'-Ti a rie-Y o l" the
instru'.ent as r:Ounted on a tri-pod ready for use, and
on page 31 a sectional dra^?ing shewing its construc-
tion and r.ethod of operation.

The ohi ect in designing this instnx'.'ent v/as
tc elir.inate the chief c^-ec-'ions of the ordinary
piston t--pe o^ indicator for hirh speed-^ , such as
the inertia oT t^ie rsciprccatin- parts, strctcliing
of the indicator cord, etc. Tlie inarc graph can
he success rully used for indie- tin- hirh-spee". in-
ternal cor;-u3tion engines or even the ordinary high-
speed stenn: engines ^ -::-_ere the crdinai"' in-licator
'.vould he practically useless.

Tiie nanograp':'. consists pri-'.arily o" -- light-
ti-ht ce'^.ar "bore about 3P centir.eters in length ^nd
having an internal cross-section of 10 hy 13 centi-

ABMOtJB
JQISIIXUaVE OFT£CSNOI.OaX

ARWOtTB
ajSTlXUTE OF CECHNOUoaX

-30-

metsrs. At the front end of tliiT wooden "box guides
are arrn.rged ~o that either a 9 "by 1"^ centirnetor
plate-holder rr.ay l:e slid in or a frane containing a
9 hy 1*^ centimeter ffrcjnd rrla-ss screen. Ahout 9
centimeters froi-: this end there is a circular hrass
"bracket inserted in one of the sides. "h.e tuhular
portion of this hra.chet has an intern-^l diarr-eter of
3 centimeters hut the inner end is closed "" ' a thin
"brass plate harin^ an orifice of 9 millineters di-
a":ieter. A tu'ifular T slides inside the hrass
tuhe , the run of the T ':ein~ vertical. This por-
tion cnrries a small acetylene hurnsr th^ hairfit
of which in the tvCcB nay he adjusted as desired.
Inside the outlet of the "^ there is n plate con-
taining- a small hole, the distance of this plate
fro~ the source of li<sht hein~ adjustahle. The
ravs of light which pass thru th- pin-hole a.re re-
flected from a triangxilar flint glass prisr. as
sho^-m on the drav>-in!5:, onto a concaTe mirro !', hav-
ing p diameter of ahcut l.*^ centimeters. The
prism m.a^'- he rotated a ■^mall am.cunt eitlier hoi"on-

AKMOTTH
JDNSTIXUTB OF 'jrBOHNOI.OOT

tall-.- or rertic^.ll- thus allov.dn^ the operator to
properl^' focus the ra--- of 11 ^ht upon the ground
glass screen. The sr.all mirror ■" !=•■ -^orinted on
an L-shaped hardened steel piece resting upon two
steel -ooints and a spherical knoh. One of the
points is secured to the ':rass fitting ^t the end
of the mpnorrap"-: and the tip of the point rG-;ts in
a conical '-ole at the turn of the L, '"ertically
helov^ this pWct point is the spherical hno''.: v;hich
presses against the vertical hnife-ed.Te in the low-
er part of the L. To the left of the pivot point
the other ^teel "coint moves in a slot cut in the
horizontal portion of the L.

The s-oherical knoo r.oves longitudirallv and,
-c'' so doing, neves the mirror ahout a horizontal
a::i3, thus crivino; a vertical m^ovement to the re-

"l3Ct9d ":ea-^ of li-ht and prohacin^- the pressure
ccmporen": of the indicator dian-i-am. T'-i'^ knoh

is at the end of a s-mall spiral? , ahout ' cent:-
r.eters in len.-rth an;' -3 mlllinet'-rs in dia-'.eter,
wriich r'-'Sts a'^ainst the center of n steel diaphram,

-33-

a'^^out 3 centimeters in di^^'-etr. 'T'his diaphragms
is su":.1ect to the pressure in tho en^iiro cylinder,
'bein'- connected to the s^^ne Tsy r.eans of -■ long
fle-lTole copper tu'oe. The difiphranK?; are sup-
plied in various thic^'-nesses , th3 sc"le~ of each,
of course, hoin'r different. ^^.ese are cali^^rat-
ed Toy the r.alcors and several are supplied Virit'i the
r.anoTraph.

T'r-ie horiscntal cc-ponont of the diagrar. is
o'ot-^.ined hy rot-tin'^ tho r.iirror acout a vertical
a-:is for.:-ed hy the lcnif3-cd,^e -nd the station-ry
po-nt. This desired rotation is produced hy "he
lonritudinal rr.otion of a steel spin-le •.■dii':;h is
driven ".y a lever IT, in turn moved h"' the crank IT.
T>e pinion T; meshes v/ith the pinion C -.diich is set
eccentric in the ^:rass piece 7^. R may he rot-ted
hy the shaft f? on -.rhich there is a --orr. meshing
v;ith F.. A flexible shnft eonn';^cts -.rith the pin-
ion C, the other end of this hein- attach-d to the
eng-ine cranh- shaft hy r.eans of a one-point clutch.

To (^et the -.anopraph in phase -rif- the engine,

that is, vo iret the en.l of the c-^.rA to corrospond
to the end of the pi^.ton travel, ^ is turned
thus cha.ngiRr the relative position of the two pin-
ions Band C. '"lien the instrutnent is in phase the
cor.pressicn lines will "be apprcxiir-atelv coincident
v/hen the ignition is shut off or when the ^.park is
sot very late.

It was found that v;ith lomr pressure connect-
ions the results ohtained could not he d-^pended up-
on as the volume o? the tuhin.s- vf^.s sufficient to
n-iaterially chnnp;^- the cle -trance of the engine.

?.espectfull7 suhr.itted,

Chica^'TC, 111. ^ uM/>-<^ // V

.^une 1, 19C8.

-I-

Pou-r-O Tc 1 e Av.to "^r.c^ina s .
("Yo-" "'orseless *'^e. )

Mr Cooling:

Air coo:i:"ng of autcv.io'bile engines,. 19 - 7-:-='.

CarVaration:

Tar'buration - Its solution, 18 - -31.

T'xperim-ntalinvecti-ation o? carljv.retors , ?.0 - 879.

Car'buration a': an experi:Ti3r.tal stud.7, 19 - 705.

Tlie la\7 of carlraretor action, 21 - 39'".

A stud''- in carljuration, ^1 - ^^89.

"Opera-" ion, Car- and T.epair of Autor-^'bile-" , r.. 11"^.

Compression:

It- useful limits and pro'ca-lo tendencies.,; IS - Oco. 17

Be sign:

P.^tion^l' ca:m design, 13 - S-"^.?. Points in autor.:ol:ile

C^jr.s and ca?r.-3-.afts , 21 - 19^1 . motor design, 18-577.

Connectin^-^^.od'-;.
Connecting-rod ds-ign, 1? -4^1, 19 - 521.

Cran!'--Ca3 33.
Totes in cran'c-case design, 20 - 74^.

C-eneral.
Biscussior. on deni-m of autorr.olDile •".otors, 18 - ^^59.
Autono'':ile engine dssign frorr. '^on. prac'-ice, 18 - 589.
TTae theor-' of'l05'^>es in four-CTcle engines, 20 - 7'9.
"^le "balancinr 0? engines, 19 - 73;",
'^urnint^ -.-.-o-'cnt and its ef ."ect on vi"- rati on and

?l-g-.7heel size, 21 - 511.

Inlet Pining.
On :-.mlti-c .finder inl-t rani ""old- , 21 - 29,

-II-

BI-LlOr-PAHrf.- -on-t'd.

Pistons.
Piston length an-l \in-ist-pin location, 18 - 555.
Periodical "motion of --soline engine pistons, 18 - 11.

rh^rts, Cranlc.
Calculation of sh-'ft ■j'.inensions , '1.^ - Hept. 5.
On the desi/n- "nd construction of crarJi-:;liafts, 21 - 317
Ho-ne e-'-ain-oles of ^•■ro>en cran^c- shafts - Trie lessons

thc-r teach, "^1 - 191.

(Cylinders.
Offset cylinder-, IS - r^ept. 19.
Cylinder stresses, 20 " P^."^,
Points ir: c-'^lir.dBr desim'i and nanufacture, 21 - 133.

■r^fficienc":

"iffh or lci'7 heatine- valuo in thei-maj efficiency'"

calculations, 19 - 13i .
Irr.^royi'"'' the thermal ef ii'icienc-r of ex--a.osion

r.otors, 18 - '^99.
The speed of c-reatsst fvel sconorr.y, 21 - 4 31.

"^^c^r^aus t , AuT'i 3 i ary I

The p.u-iliar"- exhaustoport , 18 - ~18.

PTdiaust -ases:

Anal -sis of e-haust rases, 19 - f^l?.

Fuel-:

Alcohol as a motar car f ual , '^0 - 715.

P.educin;^ fuel consumption, 19 - 7iO,

The addition of 0"-'-^en carriers to fuel, 19 - 732.

Prei-nition o ' h-'dro-carhon r-.i-tures , 19 - -99.

-III-

}3I3LI0rn',.H'Y. - "or-t ' d.

Ignition:

f^tarting on tho sparh, 18 - ^ept. 5.

Tlffect of character of spa"!: or. -^O'-'Q^r of orrine, 19-150,
Current consu:-;:ptlon of spark coils, 19 - 18=i .
Conditions of i?r.iticn in internal co"Vustion

on-ine^, 19 - 30:5, 19 - 337.
iTT.portance of usin^r proper ir^iition roltage, 18 - 305.
Spark le- \ IS - 6" 7.
::a'meto Igriition, "^O - 54 '^.

So'Vie facts pertaining to electric ignition, "^6 - 228.
C3rlindcr v/all teinperaturss , 20 - 195.
r^ingle spark ignition, '^1 - 51-,

An ignition s-^orage ■battery c-iar~in- '-.^t, ""1 - 30",
Perfecting au'-onooile ignition, '"'l - 214.